Hydraulic press



Aug. 2l, 1956 E. SIEMPELKAMP HYDRAULIC PRESS Filed May 26, 1951 INVENTOR.

EUGEN SnEMPELKAn/IF? A from/.EK

United States Patent O HYDRAULIC PRESS Eugen Siempelkamp, Krefeld, Germany Application May 26, 1951, Serial No. 228,490

3 Claims. (Cl. 100-46) The present invention relates to a hydraulic press, comprising a plurality of actuating pistons or plungers which are hydraulically operated individually or in groups and, if desired, at different pressures in contradistinction to conventional presses in which all pistons are operated together and subjected to the same hydraulic pressure.

It is an object of the invention to provide a hydraulic press having a presser member actuated by a plurality of individual hydraulic plungers or groups of plungers, each plunger operating in a hydraulic cylinder, which cylinder or group of cylinders is individually supplied with pressure fluid by an individual pump unit, whereby each plunger or group of plungers can be controlled individually. The presser member can thereby be forced to assume various positions relative to its countermember, and these positions can be changed while the presser member is in motion. If the press is used, for example, for pressing a fibre pulp, the mechanism according to the invention permits squeezing the pulp at first from one side to another by moving the presser plate flrst at an angle to the counterplate and thereupon parallel to the counterplate.

The mechanism according to the invention atfords application of different pressures at dilerent parts of the presser plate whereby the position of the latter can be maintained parallel to its counterplate although the resistance of the work to compression is different at different parts of the plates.

It is an object of the present invention to provide a hydraulic press having a presser member actuated by a plurality of individually operated actuating means and individual control means for the operation of the actuating means, which control means are responsive to the relative position of diiereut parts of the presser member. These control means, for example, throttle or interrupt pressure fluid supply to the hydraulic plunger actuating such parts of the presser member which tend to move ahead of other parts. In this way, the presser member is moved along a pre-determined path irrespective of the resistance produced by the work piece, and undesired pressures cannot occur in the guides for the presser member or act on the frame of the machine. The invention permits omitting such guides altogether and moving the presser member in any desired position relative to its countermember and changing its position while it is in motion. Different pressures can thus be applied to different portions of the work, and the compressing effect on the work can be changed for different portions of the work while it is pressed.

A further object of the invention resides in the provision of a hydraulic press in which the operation of the presser member by a plurality of hydraulic operating means is made independent of failure or unequal Working of said operating means as caused, for example, by leakage of individual conduits, valves, improper operation of individual pumps or their motors, etc. Failure of the pump or actuating means moving one side of the presser member and continued operation of the means for "ice another side of the presser member would cause damage not only to the work but also to the machine. This is eiectively prevented by the present invention which provides a control means connected with the tool, for example, a plummet or a rod which is moved in a guide adapted to close electric contacts or actuate pilot valves whenever the position of the tool, for example, the presser plate, deviates from the desired position. Conventional means operated by the electric current controlled by the contacts or a pressure uid controlled by the pilot valves will then adjust the energy supply to individual actuating means of the tool or presser plate, until it has assumed its desired operating position. The control mechanism may be modified to open instead of close electric contacts at improper positions of the tool.

lf the invention is applied to relatively large presser plates which are operated by a plurality of plungers, the operating means supplying pressure uid to the individual plungers are so controlled that, upon deviation of the position of an axis of symmetry of the plate from its desired position, supply of pressure fluid to some of the plungers is throttled or interrupted until the axis is again in the desired position. Likewise, if an axis of symmetry of the plate, extending at an angle to the rst axis, deviates from its desired position, the supply of pressure uid to other plungers is interrupted, until the second axis of symmetry is again in the desired position. Preferably pairs of plungers or rather their cylinders are served by the same operating means or pumps, and their is such a pair at each end of each axis of symmetry.

Further and other objects of the present invention will be hereinafter set forth in the accompanying specification and claims, and shown in the drawing which, by way of illustration, shows what I now consider to be preferred embodiments of my invention.

in the drawing:

Fig. l is a fragmentary diagrammatic vertical crosssectional view of a hydraulic press mechanism according to the invention; the view being taken substantially on the line I-l of Fig. 2.

Fig. 2 is a fragmentary diagrammatic vertical longitudinal sectional view of the press mechanism shown in Fig. l, the View being taken along line Il--II of Fig. l;

Fig. 3 is a diagrammatic horizontal sectional view of the mechanism illustrated in Figs. l and 2, the section being made along line III--III of Figure 2.

Like parts are designated by like numerals in all figures of the drawing.

Referring more particularly to the drawing, the press mechanism comprises eight hydraulic actuating means whose cylinders are designated by numerals 1, 2, 3, 4, 5, 6, 7, and 8. Each cylinder contains a plunger l', 2', 3', 4, 5', 6', 7', and 8', respectively, carrying a presser member or table 9 which must be parallel or at a predetermined angle to a movable or stationary counter-table, not illustrated, at all operating positions of the mechanism. Four operating means are provided for individually operating groups of two of said actuating means, Each operating means comprises a pump, pump 10 supplying cylinders 1 and 2, pump 11 supplying cylinders 3 and 4, pump 12 supply cylinders 5 and 6, and pump 13 supplying cylinders '7 and 3.

For maintaining the desired position of the longitudinal axis of symmetry of table 9, a rod member 14 is connected therewith and extends slidingly through a substantially horizontally guided control member 15 (Fig. 2). If the longitudinal axis of table 9 deviates from its desired position, the right or left end of member 15 makes contact at 16 or 17, respectively. For maintaining the desired position of table 9 transversely to its longitudinal axis, two additional vertical rod members 18 and 18 are connected with the table each of the last mentioned members extending slidably through a horizontally guided control member 19 and 19', respectively. If the table tilts about its longitudinal axis, the right or the left end of members 19 and 19', as seen in Fig. 1, makes contact at 16 or 17 and/ or 20' and 21', respectively. Closing contacts 16 and 17 effects energizing of conventional means for controlling the motors 11 and 10" operating the pumps 11 and 10, respectively, serving the actuating means or hydraulic cylinders at opposite sides of the presser member 9. Likewise, closing contacts 16, 17 and/or 20', 21' causes energizing of conventional means for controlling the motors 12', 13 operating the pumps 12 and 13, respectively. Supply of pressure fluid is throttled or interrupted until the contacts are again disconnected, i. e. until the table 9 is again in the desired position. The control of the pressure fluid supply from pumps 10 and 11 is independent of the control of pumps 12 and 13, and the control means 18 to 21 operate independently of the control means 1S to 21' for producing the desired rectifying effect on the table 9.

For returning the presser member to its original position, the pressure fluid is drained from the hydraulic cylinders. The drain pipes of all cylinders may be connected and a single drain valve be provided for all cylinders. Due to the weight of the presser member and pistons connected thereto, the former is returned to its original position by gravity.

While I believe the above described embodiments of my invention to be preferred embodiments, I wish it to be understood that I do not desire to be limited to the exact details of design and construction shown and described,

for obvious modifications will occur to a person skilled in the art.

I claim:

1. A hydraulic press comprising, in combination, a movable presser member having a longitudinal axis, at least four hydraulic pistons connected with said presser member on one side of its longitudinal axis, hydraulic pistons connected with said presser member on the other side of its longitudinal axis, an individual cylinder for each of said pistons, individual pump-motor units, at least two of said cylinders of the pistons on one side of said longitudinal axis being connected with one of said units, at least two of said cylinders of the pistons on the other side of said longitudinal axis being connected with a second of said units, the cylinder of an additional piston on one side of said longitudinal axis and the cylinder of an additional piston on the other side of said axis being connected with a third of said units, the cylinder of yet another piston on one side of said axis and the cylinder of yet another piston on the other side of said axis being connected with a fourth of said units, and control means responsive to deviations of the position of the movable presser member from a desired position and being individually connected with said units whereby said units may selectively actuate said cylinders and pistons in response to said control means to rectify said deviations of the movable presser member.

2. A hydraulic press comprising, in combination a movable presser member having a first and a second axis of symmetry lying in a plane, a plurality of independent groups of hydraulic operating means connected with said presser member for moving it, at least one of said groups being disposed on one side of a first axis of symmetry of the presser member, at least another of said groups being disposed on the other side of said first axis of symmetry, at least a third of said groups being disposed on one side of a second axis of symmetry of the presser member, and at least a fourth of said groups being disposed on the other side of the second axis of symmetry, an independent pump-motor unit connected with each of said groups of operating means, a plurality of rods individually connected with and extending transversely to the plane of the presser member, and a switch means individually actuated by said rods upon deviation of the position of the movable presser member from a desired position, said switch means being individually connected with said units for individually controlling the latter independently of each other.

3. A hydraulic press comprising, in combination, a movable presser member having a first and a second axis of symmetry lying in a plane, and tiltable about each axis of symmetry, a plurality of independent groups of hydraulic operating means connected with said presser member for moving it, at least one of said groups being disposed on one side of a first axis of symmetry of the presser member at least another of said groups being disposed on the other side of said first axis of symmetry, at least a third of said groups being disposed on one side of a second axis of symmetry of the presser member, and at least a fourth of said groups being disposed on the other side of the second axis of symmetry, an independent pumpmotor unit connected with each of said groups of operating means, at least two rods connected with and extending transversely to the plane of the presser member, and a plurality of switch means connected with each of said rods, the switch means connected with one of said rods being adapted to be actuated upon tilting of said presser member about one of said axes of symmetry and the switch means connected with the other of said rods being adapted to be actuated upon tilting of said presser member about the other of said axes of symmetry, said switch means being individually connected with said units for individually controlling the latter independently of each other.

References Cited in the tile of this patent UNITED STATES PATENTS 996,692 Webb .Tuly 4, 1911 2,283,447 MacMillin et al May 19, 1942 2,309,944 Flowers Feb. 2, 1943 2,343,167 Bench Feb. 29, 1944 2,377,007 Hess May 29, 1945 2,565,639 Woldie Aug. 28, 1951 FOREIGN PATENTS 484,313 Germany Oct. l5, 1929 

